The medical benefits of far-infrared radiation on the living body have been known for a long time, and therefore, there are far-infrared devices on the market for improving human and animal health. Most of these devices produce far-infrared radiation by using ceramic materials. In order to generate far-infrared radiation at intensities suitable for therapy or sterilization, the ceramic materials must be heated to high temperatures, sometimes few hundred degrees C. This limits the use of existing far-infrared devices in many hygienic-therapeutic applications, for example, using them for dental oral care or hair care to kill bacteria and microbes, and to rejuvenate teeth, gums and hair. In addition, the generation of far-infrared radiation in these devices is not energy-efficient; efficiencies typically are only a few percent or less. Therefore, there exists a strong need for hygienic-therapeutic far-infrared devices which will produce intense far-infrared radiation with high efficiency, and would operate at relatively low temperatures.
The devices with ceramic far-infrared radiation sources might also cause some health problems. Most of the ceramics are made from powder or clay and during their use, the ceramic materials can chip off (erode) from the surface and can be inhaled by the living body. Therefore, there is a great need for intense infrared radiation sources that are more environmentally safe and do not expose humans or animals to health risks.
Another limitation of the devices with ceramic far-infrared radiation sources is fixed radiation spectra which cannot be changed to increase the effectiveness of therapy. The living body is most influenced by infrared radiation within the wavelength range of 8 to 12 microns and many currently used devices cannot deliver radiation at this spectral range.
To mitigate the previously stated issues of using ceramics as far-infrared sources in hygienic-therapeutic devices, this invention proposes to use novel conductive sources emitting intense far-infrared radiation with a high conversion efficiency of energy to radiation, typically greater than 90%. In nature, conductive materials follow the “black body” radiation phenomenon and they do not emit intense far-infrared radiation. However, there are some conductive materials, like carbon fiber and other materials proposed in this invention, which emit very intense far-infrared radiation with extremely high conversion efficiencies of energy to radiation.